Objective: To compare the efficacy of two starting protocols of multiple dose GnRH antagonists (GnRH-a).
Design: Prospective randomized controlled study.
Setting: In vitro fertilization-embryo transfer program at the Instituto Valenciano de Infertilidad, Valencia, Spain.
Patient(s): One hundred nine patients undergoing controlled ovarian hyperstimulation (COH) with recombinant gonadotropins and GnRH-a (0.25 mg/d).
Intervention(s): Patients started GnRH-a administration on stimulation day 6 (group 1) or when the leading follicle reached a mean diameter of 14 mm (group 2).
Main outcome measure(s): Implantation and pregnancy rates; serum E(2) and LH levels during ovarian stimulation; days of stimulation and GnRH-a administration.
Result(s): Days needed for ovarian stimulation were similar in both groups but there was a significant difference when comparing days of GnRH-a administration. Serum E(2) and LH followed similar curves in both groups. Implantation and pregnancy rates were 23.7% and 44.4 % in group 1 and 28.6% and 50.9 % in group 2 (P=not significant [NS]).
Conclusion(s): The efficacy of the two starting protocols of the multiple dose GnRH-a evaluated in this study is similar; however, this remark can only be drawn for a selected group of patients.